Automotive speed control system



Sept. l5, 1970 R. H. THQRNER AUTOMOTIVE SPEED. CONTROL SYSTEM originalFiled Feb. a. 1965 4 sheets-sheet 1 INVENTOA f y af@ r/ Wag/VEP v f R.H. THRNER sept. 15 1910 UTMOTIVE SPEED CONTROL SYSTEM Original FiledFeb. 8I 1965 4 Sheets-Sheet 2 INVENTOR. Po/35x27# 10e/vf@ a. H. THQRNER3,528,523

sept. 15,1970

AUTOIOTIVE SPEED CONTROL SYSTEM v original Filed Feb. a. 1965sheets-sheet u 'Sept 15, mo R. MHQRNER 3,528,523

. AUTOMOTIVE SPEED connor; SYSTEM. l

original Filed-Feu a, 1965 4 sheets-sheet d I INVENTOR. 055,477# img/v5@United States Patent O 3,528,523 AUTOMOTIVE SPEED CONTROL SYSTEM RobertH. Thomer, S750-F W. Chicago Blvd., Detroit, Mich. 48204 Originalapplication Feb. 8, 1965, Ser. No. 430,910, now Patent No. 3,343,423,dated Sept. 26, 1967. Divided and this application Sept. 15, 1967, Ser.No. 668,121 Int. Cl. B60k 31/00 U.S. Cl. 180-105 10 Claims ABSTRACT OFTHE DISCLOSURE The main disclosure herein comprises an automatic speedcontrol including mechanism providing a selective mode of operationwhich enables the driver when he chooses to resume a previously setregulated speed subsequent to slowing or stopping the vehicle. Thisselective control mechanism enables automatic reactivation of thespeed-control device in response to a change in accelerator movement andis accomplished by advancement of the accelerator slightly beyond normaldriving to initiate automatic acceleration to the regulated speed. Aparticular form of the invention for this mode of operation includes uidrestriction mechanism acting on the speedsetting spring of the governormechanism to delay the change in the force of the spring, thereby torestrict the rate of automatic acceleration to safe values. Anotherresult obtainable with this delay mechanism when desired is to enablereverse or negative speed-droop with stability, which can provide asubconscious surprise to reduce the tendency for highway hypnosis.

The present application is a division of Ser. No. 430,910, filed Feb. 8,1965, entitled Automotive Speed Control System, now Pat. No. 3,343,423,which contains subject matter relating to the inventions disclosed in myfollowing patent applications: Ser. No. 283,272, led May 27, 1963,entitled Speed Regulating Device, which is a divisional case of Ser. No.74,315, liled Dec. 7, 1960, entitled Vehicle Speed Regulating Device,now Pat. No. 3,153,325; Ser. No. 82,769, liled Jan. 16, 1961, entitledSpeed Regulator Device, now Pat. No. 3,213,691; Ser. No. '118,411, tiledJune 20, 1961, entitled Throttle Control Mechanism, now Pat. No.3,168,933; Ser. No. 266,257, filed Mar. 19, 1963, entitled AutomotiveSpeed Control Apparatus, now Pat. No. 3,305,042 and Ser. No. 316,987,liled Oct. 17, 1963, entitled Automotive Speed Control System, now Pat.No. 3,222,227.

With the increasing use of non-stop highways, sometimes referred to asturnpikes, thruways, freeways, etc., there is an increasing need for anautomatic throttle for automotive vehicles. When an automobile is drivenfor long distances on these non-stop highways, the operators foot andleg muscles become tired and strained due to the necessity of holdingthe accelerator in various desired positions for long periods of time. Amain purpose of all automatic throttle devices, as disclosed herein, isto enable the vehicle operator to drive without the necessity ofholding'his foot on the accelerator. Such devices are now believed toadd safety in operating automotive vehicles because (l) they reducefatigue, thereby reducing the tendency to fall asleep, (2) they maintaina selected speed, whereas in normal driving it is easy on long trips toexceed the intended speed unknowingly.

At the present state of the art, there is a wide difference of opinionamong people at the automotive firms regarding what is desired for suchspeed control devices. These devices generally comprise (l) some type ofmeans to regulate vehicle speed, either automatically (with a governormechanism) or manually (hand-throttle), and (2) rice a selective controlsystem to determine when and how the speed-regulating means is operatedand rendered inactive or inoperative, and also to select the operatingspeed, etc.

A large difference in opinion exists particularly in the selectivecontrol system for the governing mechanism. Some of my present beliefsare discussed extensively in said application, Ser. No. 266,257. Some ofthese views, of course, may have to be altered in accordance witheventual public opinion, because of ultimate acceptance or rejection ofthe various systems offered. However, based on public acceptance todate, I presently believe that the eventual market will be large enoughto support at least two basic automatic governor-type speed controls inaddition to a good manual speed control (or handthrottle). 'Ihe firsttype of device is presently available to the public and comprises aquality speed control system. Such devices probably will nd its largestsale on medium priced and luxury vehicles, and possibly for luxurymodels of lower priced vehicles. My said application, Ser. No. 266,257discloses a control system that might fall in this category, as itprovides features desired by some people (such asaccelerator-resistance) who would pay a premium for such features. Mycentrifugal-liquid sensing and the governing system disclosed in myPats. Nos. 3,068,849 and 3,084,758 provide such excellent governingcharacteristics to qualify as a quality governing device.

In certain regulator applications, such as for an automotive speedregulator in turnpike driving, reduction of cost is highly critical inorder for such devices to gain wide public acceptance. Such desirablereduction of cost can best be achieved by inherent simplification of themechanism, which may be justified even at some compromise in performancefrom that produced by the structures disclosed in my said co-pendingapplications. I believe that the eventual market will support a secondeconomy" speed control system in addition to the quality systemdiscussed above. Such economy device will include a true closed-loopgoverning mechanism and a control system therefor, but all with certaincompromises to enable low-cost manufacture. Such a device will desirablysell to the consumer at a price somewhat less than the price of thequality device.

A main object of the present invention is to provide a governor-typespeed control system for an automotive vehicle particularly, but notnecessarily, for carbureted internal combustion engines and which isvery simple in construction thereby lending itself to low costmanufacture, and also disposed for simple installation in any kind ofautomotive vehicle.

All automotive speed control devices now otered commercially either mustbe manually reset after each brake actuation or the vehicle isautomatically placed under control of the speed regulator only if andwhen the preset governed speed is attained. With the latter type controlsystem, the vehicle driver, after turning the ignition key to its onposition, must manually set the regulator control at least once in orderto enable automatic operation; thereafter, the driver must wait until hemanually accelerates the vehicle to the actual preset regulated speedbefore he can remove his foot from the accelerator. When the brake isdepressed, the speed regulator is inactivated, but again the presetspeed must be attained before the speed regulator again assumes controlof the engine. After braking the vehicle to a stop, the speed regulatoris rendered inoperative by restraining means operated upon turning 0Ethe ignition switch, so that the next driver must manually activate thespeed control once after turning on the ignition switch.

The present invention relates in part to a novel control system for anautomotive speed regulator mechanism which provides a vastly improvedoperation over the present control systems described above. The mainutility of the control system of the present invention is to enableautomatic activation of the control system only after partial butselective temporary advancement of the accelerator at a low speed, andthen to provide completely automatic acceleration up to the preset speedat any time the driver chooses to employ such automatic activation. Whenthe accelerator is deliberately and selectively advanced partially bythe vehicle-driver, wherein the vehicle attains a speed somewhat lessthan the preset speed, the speed regulator device is activated andamomatl'cally accelerates the vehicle moderately to the set speed. Thisautomatic acceleration action is more desirable than the action ofpresent control systems as above described because (l) the operator doesnot have to wait until the set speed is attained each of the many timesthe device must be engaged in normal driving, and (2) thevehicle-operator can remove his foot from the accelerator and thevehicle will automatically seek out and stop accelerating at exactly thepreselected speed in each of the many times the speed-governor actionmust be inactivated and re-activated in normal driving, and (3) by usingthe Braille system of speed selection, the vehicle-driver never has tolook at the speedometer once he has learned the clock positions of thespeed-setting knob, as will be described.

In actual practice I have found that these advantages greatly expand theuse of such speed control apparatus to include city and particularlysuburban driving (on main fast streets and boulevards), between therushhours of traffic, as well as for highway and turnpike driving, to bediscussed further. This is true because my control system providesautomatic acceleration in addition to automatic engagement. In boulevarddriving in light traic, it frequently requires about one-half thedistance between stop lights to attain the preset speed; hence, in thisexample, not more than one-half of this distance can be under automaticcontrol. I have found that in clear or light traffic about 90% of thistravel can be under control of the speed regulator. In general, I havefound that driving an automotive vehicle with the type of control systemdisclosed herein, increases the utility and driving pleasure to a degreewhich is very difficult to convey in Words.

In order to achieve this highly desirable result, many puzzling problemshad to be solved. It is essential that the system be completely safe andthat no driver is ever surprised or startled suddenly by automaticacceleration when unexpected. For this reason, the ignition switch (orany other factor of engine operation) by itself is not acceptable as ameans for operating the restraining means to render the speed controldevice inoperative because it would not detect a change in drivers atall times. This is true because the driver frequently leaves thev'ehicle while the engine is idling, and the next driver might bedangerously surprised when he advances the accelerator entirely unawarethat the vehicle can be automatically engaged and accelerated.

My hand-throttle devices (such as Ser. No. 118,411) inherently produce aslow acceleration after automatic engagement. But governor or similarclosed loop speed control devices tend to accelerate the vehicle ratherrapidly, and under some circumstances can produce a dangerous roar ofthe engine that can startle the operator. Accordingly, a second problemis to provide that the rate of automatic acceleration is moderate.

Another puzzling problem in providing safe automatic acceleration isthat the automatic activation or engagement cannot be speed-responsiveas provided in present speed regulator devices. For example, assume thatthe regulated speed is set for 60 m.p.h. and the automatic engagementalways occurs at 30 m.p.h.; and the vehicle is accelerated automaticallyto the preset speed each and every time this lower speed is attained.This type of automatic engagement and acceleration would occur at alltimes, even if the driver does not want or expect it; furthermore, theautomatic engagement'would occur at the same speed every time. Thecontrol system of the present invention is made selective since theautomatic engagement occurs as a function of advancement of the throttleat the discretion of the driver completely independent of vehicle speed.I have found this method to be truly selective since the activation orengagement can be made to occur at any desired speed below (or evenabove) the preset speed.

Thus, in order to make this desirable control mode of operationavailable to the public, it is necessary to provide ample safety meansto preclude any possibility of a surprise factor in anydrivingsituation. Ample safety means are disclosed herein as will be described.

A very important object of the present invention is to provide a controlsystem for an automatic throttle governor or speed regulator mechanismin an automotive vehicle, as recited in the preceding object, whichrequires the operator to partially and temporarily advance the controlmeans deliberately in order to effect an automatic engagement oractivation of the speed governor mechanism; and wherein such engagementis indicated to the operator by signal means dependent on the senses ofsound and/or touch, and he then can remove his foot from the acceleratorsubstantially before the set speed is attained; and thereafter the speedcontrol apparatus effects automatic acceleration of the vehicle up tothe preset speed, and such speed is automatically maintained thereafterin all vehicle attitudes.

In the automatic acceleration feature of the present invention as statedabove, when an automatic speed governor mechanism is included, a highrate of acceleration is sometimes produced which is hazardous. In myhand throttles, such as disclosed in said application Ser. No. 118,411,the rate of automatic acceleration is inherently slow and hence I havefound such devices to be completely safe for automatic acceleration. Mysaid applications, Ser. Nos. 74,315 and 82,769, disclose automaticacceleration which is effected after partial advancement of the controlmeans. Means are disclosed in my said application, Ser. No. 266,257, toretard the rate of automatic acceleration comparable to the inherentrate of acceleration with my hand throttle devices or to theacceleration with normal safe driving of any automotive vehicle.

Another object of the present invention is to provide an automotivespeed control apparatus including a control system, as above recited,and also an automatic speed regulating mechanism, in which novel meansare provided utilizing an inherent characteristic of manifold vacuum (ofa carburetted internal combustion engine) without added mechanism toeffect a retarded or safe rate of automatic acceleration.

Another important object of the present invention is to provide anautomotive speed control apparatus including a control system, asrecited in the second preceding paragraph, and also a speed regulatingmechanism, in which novel mechanism is provided to retard the rate ofautomatic acceleration upon engagement or activation of the speedregulating mechanism and become ineffective upon attaining thepreselected speed after said automatic acceleration.

An additional object of the present invention is to provide anautomotive speed-control system as described in any of the precedingparagraphs, including a simple speed governor or regulator mechanismwhich includes novel means to enable automatic operation thereof onlyafter the vehicle is manually accelerated to a speed slightly above theidle speed but below the lowest governed speed, wherein the regulatormechanism cannot be operated when the vehicle is at rest.

Still another object of the present invention is to provide a speedregulator mechanism for automotive vehicles in which novel reset meansare provided to render the mechanism completely surgless at any desiredspeed droop;

and further to enable the use of a reverse or negative speed droopwithout surging which provides a repeating factor of surprise to thedriver intended to reduce highway hypnosis in turnpike driving.

Another object of the present invention is to provide an automotivespeed control apparatus including a control system, and an automaticspeed regulating mechanism in which restraining means are providedoperable, in one form, upon opening the vehicle door to render theautomatic speed regulating mechanism inoperative until deliberatelyactivated by the vehicle operator after entering the vehicle and closingthe door; and in other forms such restraining means may be operated bythe transmission manual control lever, or by the vehicle seat, or anyother such vehicle element normally operated manually and selectively bythe vehicle operator incident to his leaving or entering) the vehicle.

Another object of the present invention is to provide an automotivespeed-control system of the type described in the preceding paragraphsand having a carbureted internal combustion engine, in which enginevacuum is used as a source of energy in operating the governor system,and in which a supplemental restraining means may be provided to enablethe vacuum itself to maintain the system operative (after manualinitiation by the vehicledriver), but automatically renders the systeminoperative whenever the engine vacuum dissipates, for example, as aresult of turning olf the engine ignition.

Another object of the present invention is to provide in a controlsystem for automatic-throttle operation in an automotive vehicle, andincluding a speed governor mechanism, novel means to permit actuatingonly the control means of the engine independently of the acceleratorand linkage therefrom, but providing normal operative connection of theaccelerator and engine control means when the governor mechanism iseffectively inactivated.

A further object of the present invention is to provide a control systemfor an automatic-throttle mechanism in an automotive vehicle as recitedin the foregoing paragraphs in which all of the control functions oroperations may be accomplished by various movements of a single knob ordial, and to include tactile indicating means, if desired, so that onlythe sense of touch is required by the 4operator without removing hissight from the road.

Further objects and advantages of the invention will be apparent fromthe following description, taken in connection with the appendeddrawings, in which- FIG. 1 is a somewhat diagrammatic view of a completeinstallation of one form of automotive speed control apparatus of thepresent invention mounted in an automotive vehicle and showing thecooperation of the control system and an automatic speed regulatingmechanism, and in which the selector means of the control system isshown in section taken along the line 1--1 of FIG. 4;

FIG. 2 is a partial sectional view of the selector mechanism of thecontrol system for'establishing the operating condition of the governormechanism as disclosed in FIG. l and taken along the line 2 2 of FIG. 3;

FIG. 3 is another partial sectional view of the selector mechanism shownin FIGS. l and 2 and taken along the lines 3-3 of FIG. 2;

FIG. 4 is still another partial sectional view of the selector mechanismof FIGS. 1-3 taken along the line 44 of FIG. 2;

FIG. 5 is an electric circuit showing the action of the restrainingmeans operated by a vehicle-door;

FIGS. 6 and 7 are perspective views of important details of theflyweight device shown in FIG. 1;

FIG. 8 is partial cross-sectional view of the centrifugal flyweightdevice of FIG. 1 taken along the line `8--8;

FIG. 9 is a partial sectional view of the brake-operated release meansincluding throttle-responsive activating means as taken along the line 99 of the valve unit 170;

FIG. 10 is a diagrammatic view of an alternate form of restraining meansoperated by the vehicle seat;

FIG. 11 is a diagrammatic view of an alternate or supplemental lform ofrestraining means operated by the vehcle transmission lever;

FIGS. 12 and 13 are partial sectional views of a supplemental form ofrestraining means operated by engine vacuum and modified from the formshown in FIGS. 1-4 as would be seen along the line 1-1 of FIG. 4;

FIG. 14 is a fragmentary and partial sectional view of a modified formof the speed sensing means illustrated in FIG. 1 which provides aretarded rate of acceleration; and

FIGS. 15 and 16 are fragmentary sectional views of several modicationsof the form of the invention shown in FIG. l, to provide an automaticreduction of vehicle speed on highway curves.

It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangement of partsillustrated in the accompanying drawings, since the invention is capableof other embodiments and of being practiced or carried out in variousWays. Also, it is to be understood that the phraseology or terminologyemployed herein is for the purpose of description and not of limitation.

It is also to be understood that the present invention may -be used inany kind of highway or road vehicle such as for automobiles and trucks,and may control any kind of engine therein such as an internalcombustion gasoline engine or diesel engine, a gas turbine, etc. Thegovernor mechanism disclosed herein has particular utility in combustionwith the control system of the present invention. IHowever, the controlsystem may also be used with any other suitable speed governor mechanismor equivalent, or with any other kind of mechanism tending to correctthrottle position in any desired manner.

The form of the invention illustrated by the automotive speed controlapparatus shown in FIG. l Will Ifirst be eX- plained from aconstructional standpoint before discussing the operation. The speedgovernor or regulator mechanism will first be explained in its automaticoperation, and then the control system therefor will be discussed. Thevarious components illustrated in FIG. 1 are shown in workingcooperation primarily for ease of understanding and are not necessarilyshown in true proportion.

SPEED GOVERNOR MECHANISM The speed regulator mechanism illustrated inFIG. 1 includes two basic components or units, as follows: asensor-brain unit, generally indicated 'by the numeral 5; and aservo-motor unit, generally indicated by the numeral 7.

In FIG. 1 there is shown a conventional brake pedal 10 supported by lanarm 11, and carburetor 12 in an engine intake passage or manifold 14 andincluding a control member such as a throttle 16 with a lever I18,operated by an accelerator 20 hingeably connected to a iloorboard 17through a shaft or link 21 all biased in their idle-speed direction byan idle spring 24 and a lever spring 26, to be discussed hereinafter.The lever 18 and throttle 16 are operated by the speed-regulatormechanism through override or lost-motion means, illustrated in FIG. 1as a ballchain link 29 to enable actuation of lever 18 by the servomotor7. In the form shown, the accelerator linkage er1- gages lever 18 bymeans of a second override or lostmotion unit 35 having a U-shapedmember or bracket 37 carried by the lower portion of lever 18 'andhaving holes to enable shaft 21 to slide therethrough. An abutment 39 issecured to the shaft 21 to enable actuation of lever 18 by theaccelerator.

The override link means 29 is actuated by a pressure responsive memberof the servo-motor 7, such as a diaphragm 40 having atmospheric pressureon one side thereof in a chamber 42 and vacuum on the other side thereofin a chamber 44. The vacuum-derived force of diaphragm 40 is Ibiased oropposed by a servo-spring 4'6 which tends to close the throttle 16 whenthe regulator is in operation. The vacuum in chamber 44 acting ondiaphragm 40 is modulated by a pilot valve 48 (illustrated as a ball)carried by a swingable arm 49 of the sensorbrain unit supported forfrictionless modulating movements at one end thereof by hinge means,such as a leaf -spring member 50, which leaf member is rigidly mountedto a fixed portion of the sensor-brain unit by suitable means, as by ascrew.

The pilot-valve -48 controls a fluid circuit in which air from theatmosphere passes through a filter F into a chamber S2 and then flowsthrough an inlet orifice or restriction 54, `and through a passage 55 inthe sensorbrain unit 5, through a conduit or passage 56 lwhich is inopen communication with chamber 44 (preferably made of synthetic rubbertubing), then through an outlet orifice or restriction 518 in a tube 59secured to a cover 60, and out through a conduit or passage `61subsequently to the intake manifold 14 without further restrictionduring operation of the governor mechanism 'by means to be discussedfurther. The passage 61 is preferably made of synthetic rubber tubing.

The pilot valve `48 may assume any suitable contour, -but in the formshown, the ball valve is held in alignment by leaf spring 50, or otherhinge means, and is biased in a closing direction by a Speeder-spring 62for cooperation with restriction `54 to vary the aperture thereof.Spring 62 is preferably 'but not necessarily of variable rate, since theforces produced by the Weight mechanism to be described Vary as thesquare of the speed.

The pressure (vacuum) in passage 56 between the two restrictions 54 and58 is applied to diaphragm 40. A tapered re-set valve 64 may be providedto be suitably connected to diaphragm 40 and is effective upon movementsof the diaphragm and throttle 16 to vary the aperture at restriction 58as a function of the position of the throttle. The chain link 29 isconnected to diaphragm 40 by any suitable means, as by a ball in asocket. The socket includes a threaded portion 66 cooperating withmating threads of the valve 64. Adjustment of valve 64 by a screw slot67 changes its effective relationship with the throttle 16, to providespeed-droop control.

When the pilot valve 48 is held closed by Speeder-spring y62,substantially the maximum available vacuum exists in conduit 56 andchamber 44. When the pilot valve progressively is moved from its seatedposition to its full open position, by means to be discussed, the vacuumin conduit 56 and chamber 44 is modulated and gradually reduces to avalue enabling full leftward travel of diaphragm 40 caused by spring 46.The maximum diaphragm vacuum obtainable in chamber 44 during regularoperation, such as 5 to 7 inches of mercury for example, is establishedwhen the diaphragm `40 overpowers the force of spring 46 to advancethrottle 16 until the vacuum reduces enough to balance the spring. Forthe same reason, the minimum manifold vacuum obtainable in the engineduring the regulator operation is substantially the same as this maximumdiaphragm vacuum. As valve 48 gradually opens to reduce the vacuum inchamber 44 from the maximum value, diaphragm 40 gradually moves to theleft as a function of the travel of valve 48 to the left, andconversely, as shown in FIG. 1.

A novel centrifugal ilyweight mechanism having rolling weights providescentrifugal forces that vary as a function of vehicle (or engine) speed,which forces act on the pilot valve to cause speed-responsive movementsthereof as a result of changes in the centrifugal forces. The forcesproduced by the rolling weights are opposed and balanced by spring 62which is manually adjusted by axial movement of a spring retainer 76operated by a suitable shaft means inserted through a cover 77, such asa flexible shaft 80 controlled by the operator and slidable in a sheath81, to be discussed further. A bushing 82 is secured to cover 77 bysuitable means, as by staking, or is a part of cover 77. The sheath isinserted in the bore of the bushing, and secured, as by a screw.

Referring to FIGS. l, 6, 7 and 8, a housing 84 includes fixed portionsof a perimetrical surface, such as cylind.ical surface 85 having spacesto accommodate a pair of radially movable portions such as the segments86 and 88 which comprise part of the cylindrical surface. Surfaceportion or segment 86 is suitably secured to arm 49 to effectspeed-responsive movements thereof in a manner to be described. Aplurality of rolling (or sliding) weights 90, Such as balls or rollersas illustrated, are each connected by frictionless means (as by pivots)to a yoke member 92 having a knife-edge 92a. The yoke member isconnected for frictionless radial movements at knife-edge 92a to an arm94 of a rotatable spider or impeller 96. The knife edges are fulcrummedat the corners 94a of arms 94 to enable the weights to be rolled in agenerally circular path by impeller 96 which is suitably secured to arotating shaft 98 for rotation thereby; the shaft is driven by theengine or transmission and in present vehicles usually comprises theflexible speedometer shaft of an automotive vehicle. The radialcentrifugal force of each weight as it rolls (or slides) across thesurface portion 86 is transmitted to arm 49 and balanced by spring 62 toposition valve 48, which opens as the shaft speed increases, andconversely.

The speed-regulating action of the governor mechanism described thus faris as follows: When the rotary speed of the vehicle increases, thecentrifugal force produced by the roller-weights urges the pilot valve48 to the left biased by spring 62 to open the restriction 54 graduallyas the speed increases. This action decreases the vacuum in chamber 44in a modulated manner previously described, so that spring 46 movesdiaphragh 40 to the left, as viewed in FIG. l, which enables spring 26to retard throttle 16 tending to restore the regulated speed. When thevehicle (or engine) speed decreases, the regulating action is thereverse of that above described, to advance the control means andrestore or maintain the governed speed.

FIGS. 6 and 7 are enlarged perspective views of the yoke and spider arm,respectively. The yoke includes an extension 92b which projects throughslot 94b in arm 94 to maintain the yokes in position to clear the endwall '84a of housing 84 and a cover piece 100 as shown best in FIG. 8.Also, for best results, the entrance radius of portion 86 is slightlygreater than the radius of surface 85, whereas the trailing radius ofsurface 86 is slightly less than the radius of surface 85. In order toenable a smooth and continuous transfer of the rolling weights from thefixed surfaces 85 to the radially movable surface 86, the ends of eachsurface are suitably rounded or contoured for this purpose. In FIG. 8,it can be seen that the movable surface portion 86 (as well as portion88 to be discussed) completely clears end Wall 84a and cover 100. Sincethe swingable arm 49 and its leaf spring 50 are frictionless, the speedresponsive movements of all parts moved radially by the rolling weightsare completely frictionless. An important characteristic of thisfiyweight inventive combination is that the rolling weights arefrictionless in radial speed-change-responsive movements. This is truebecause all rolling friction occurs in a direction transverse to theradial direction of movement and has no component in said radialdirection. The only radial (angular) movements of the Weights and yoke92 is controlled at the knife-edge connection of elements 92a and 94a,which connection is completely frictionless in its radialspeed-responsive movements. Hence, this novel centrifugal Weightmechanism is completely frictionless, and has many useful applicationsother than for automotive speed regulating systems. However, thiscentrifugal weight mechanism is extremely simple and can operate at lowdriving torque so that the speedometer shaft is not overloaded which isan important consideration. Accordingly, while the weight mechanism hasseparate utility, per se, it has particular utility in a combination ofelements comprising an automotive speed-regulating mechanism, and moreparticularly in combination with the remaining mechanism disclosedherein because of its overall utility and simplicity.

When the centrifugal weight mechanism is used as part of an automotivespeed regulator, as illustrated in FIG. 1, it is preferable for thesurface portion or segment 86 to be mounted toward the rear of thevehicle. Then, when the vehicle is accelerated automatically, theadditional inertia forces of the weights cause valve 48 to open earlywhich effects operation of the regulator mechanism before the stablepreset speed is attained. This action results in a soft cut-in of theregulator mechanism.

As illustrated in FIGS. 1, 6 and particularly FIG. 8, the rollingweights are retained by pivots mounted in conical recesses in the armsof yoke 92. The arms have narrowed sections 92e to provide a springaction for enabling the weights to be snapped in place. As analternative, the weights may be secured to the yoke wherein the weightsslide instead of roll on the cylindrical surface; however, with thisconstruction the elements must be made of low friction materials tominimize the frictional drag on the speedometer shaft. When the vehiclemoves in a backward direction, the rotary speed of impeller 96 is verylow and the arms 94 move the weights in a reverse direction. Althoughthe rolling weights are illustrated as being pushed by the yokes 92 inregulator operation, they could be arranged to be pulled by the impellerarms 94, if desired, to provide the same rolling action withoutdeparting from the spirit of the invention.

The diaphragm 40 and spring 46 are selected to hold the throttle at itsmaximum opening at the highest practical diaphragm vacuum such as -7inches of mercury in passage 56 and chamber 44. As previously described,the necessary diaphragm vacuum is determined by the force of spring 46and the size of diaphragm 40. It is desired to use as high a diaphragmvacuum as possible, which might be termed the critical vacuum, in orderto provide sufficient force to operate the throttle and any associatedlinkages. However, as the total available manifold vacuum tends to fallbelow this critical value (as when ascending steep hills) the throttlegradually is retarded by diaphragm 40 to maintain this vacuum (while thepilot valve is closed by spring 62 trying futilely to increase thediaphragm vacuum) so that the desired regulated speed cannot bemaintained thereafter. Thus the maximum diaphragm vacuum must be chosento compromise these opposing factors. As the pilot valve 48 opens whenthe manifold vacuum is above the critical value, the diaphragm vacuumgradually reduces from its maximum as above noted by movement of thepilot valve to an amount which enables spring 46 to retard throttle 16as required. Hence the diaphragm 40 will not start moving to the left,as viewed in FIG. 1, until the vacuum in chamber 44 is reduced bymovement of pilot valve 48 to be less than the value of this criticalvacuum. Thus, if the spring 46 is selected to enable the governormechanism to maintain the governed speed at 5 inches of mercury, forexample, the size of diaphragm 40 would cause it to start moving at alesser vacuum, such as 4% inches of mercury, for example, when the pilotvalve starts to open. The total leftward travel of diaphragm 40 to closethrottle 16 might be effected when the pilot valve opens enough toproduce a still lesser vacuum, such as 21/2 inches of mercury, forexample, determined by the rate of spring 46. The foregoing concept isutilized in a novel manner to facilitate automatic acceleration at alimited rate, to be discussed further hereinafter.

When the operator accelerates the vehicle manually at a moderate ratewith the throttle producing a higher manifold vacuum, such as 12-14inches of mercury, for example, this higher vacuum acts on the exposedportion of the pilot valve and might delay its opening slightly to ahigher speed than selected. A relief or regulator valve 104 which isbiased by a light spring 106 is set to open at a manifold vacuum ofabout 6-7 inches of mercury, with the foregoing example, for limitingthe vacuum in passage 56 and chamber 44 to this value by bleeding airthereto. This vacuum is high enough to hold diaphragm 40 in its extremeright position until the pilot Valve opens.

The centrifugal weight mechanism as disclosed herein includes means topreclude operation of the speed regulator mechanism until the vehiclehas actually attained a low predetermined speed, such as 15-20 m.p.h.for example. As illustrated herein, the cut-out mechanism comprises avalve 110 cooperating with an orifice 112 to bleed air into passages 5S,56 in parallel with the pilot valve 48. The bleed valve, illustrated asrubber or the like, is secured to the radially movable portion orsegment 88, which is supported for frictionless swingable movements by aleaf spring 114, or equivalent hinge means. The assembly of segment 88,valve 110 and hinge 114 is biased in an opening direction by a lightspring 116 in opposition to the force of Weights rolling on portion 88.When the vehicle is at rest, spring 116 holds valve open to bleed airinto passages 55, 56 and chamber 44 to render the regulator mechanisminoperable. When the vehicle attains a speed determined by spring 116,such as 15 m.p.h., the weights 90 close valve 110; then at all speedsabove l5 m.p.h., the control of the regulator mechanism is determined bythe pilot valve 48 and by selector control means, to be discussedWhenever the vehicle speed falls below the illustrated speed of l5m.p.h. regardless of the reason, the regulator mechanism cannot beactivated in any manner.

When the terms pressure or vacuum are used herein, they both refer to apressure dierential. Positive pressure is the difference between apost-atmospheric absolute pressure and the atmospheric pressure. Vacuumis the difference between a sub-atmospheric absolute pressure and theatmospheric pressure.

SELECTIVE CONTROL SYSTEM Automatic throttle devices now in use are soarranged that the vehicle must actu-ally attain the set speed before theregulating mechanism can be activated. It is my intention in thespeed-regulating mechanism of the present invention to provide safeautomatic acceleration after the device is safely engaged or activatedat any speed below the set speed at which time the driver removes hisfoot from the accelerator after hearing an audible signal; and then thevehicle automatically accelerates slowly or moderately from the engagedspeed to the preset speed. Hence, the main utility of the control systemof the present invention is to effect such automatic activation onlyafter a partial and temporary advance of the throttle or accelerator.Then when the throttle is deliberately and selectively openedtemporarily by the vehicle-driver (while the vehicle attains a speedsomewhat less than the preselected speed), the speed regulator device isactivated and automatically accelerates the vehicle moderately to thepreset speed. The audible signal is produced upon such activation toindicate that the drivers foot can be removed from the accelerator.

In utilizing the present invention as an automatic throttle for turnpikedriving, I provide a control system operable preferably only after thedriver enters the vehicle and the doors are closed which enables thedevice to be initially activated by the driver. In the form shown, suchcontrol system includes a valve unit having an activation Valve operatedby movement of the brake pedal to shut olf or open the source vacuum tothe speed regulator; and as part of the control means I further provideautomatic engagement or activation means operated as a function ofmovement of the accelerator pedal or throttle which opens the valve toautomatically re-activate the regulator device after a partial andtemporary advancement of the accelerator pedal. In the forms shownherein, such automatic activation means may comprise a diaphragm exposedto manifold vacuum which opens the activation valve after the throttleopens enough to reduce the manifold vacuum sufficiently to cause suchautomatic activation or engagement.

My control system also may include a second shut-off safety valve whichis initially opened by a rst depression of the brake pedal andthereafter is held open by manifold vacuum; but the safety shut-offvalve is automatically closed whenever the vacuum dissipates for anyreason. The safety valve is again opened automatically only upon thefirst brake actuation and providing manifold vacuum again exists in thesupply tube. I also include in my control system selector valve means inthe vacuum source conduit, which valve is manually and selectivelyopened by the driver, but is automatically closed by restraining meansoperated by the vehicle door, or by other suitable restraining meansinitiated upon activation of a driveroperated movable element of thevehicle which detects a change of drivers. Manually operated (safety)means are associated with the restraining means for enabling manualoperation of the restraining means at any time to render the speedcontrol device inoperative, and precludes operation of the restrainingmeans until it is operated deliberately by the driver. Thus, in thepreferred form of my control system, the device is automaticallyrendered inoperative by restraining means operable incident to thedriver leaving the vehicle and can only be set for activation by thedriver selectively and deliberately after each time he closes the door(and if he moves the transmission lever into drive position if thisfactor is provided); and thereafter the device is automaticallyactivated finally upon a partial and temporary advancement of theaccelerator until an audible signal is heard following each temporaryinactivation of the device by normal operation of the brake pedal.

The control system, in the form of the invention illustrated herein,includes two main components for controlling the transfer of vacuum tothe tube 61 from another tube or conduit 120 (preferably made ofsynthetic rubber) to supply vacuum from the manifold 14 as a source ofenergy or power to the servo-mechanism in the governor portion of thesystem. A main component of the control system is a selector mechanismor unit, generally indicated by the numeral 122. The selector unit ofthe present invention includes a manually-operated member or meansmovable upon operation at least once by the vehicle-driver to open avalve for transferring or communicating the full vacuum from themanifold 14 through tube 120 and another tube 61 to the tube 61. Thevacuum is maintained in these supply tubes by the manually operatedmember at least when the vehicle driver remains in the vehicle or unlessthe manuallyoperated means is deliberately returned to its inoperativeposition by the driver thereby shutting off the vacuum to precludetransfer thereof to the servo-motor. If the operator fails to move themanually operated means to shut off the valve, automatic restrainingmeans are provided in which the selective movement of an element of thevehicle, such as opening a door, automatically causes lmovement of themanual means to shut off the valve; then the operator again mustconsciously move the manual means deliberately to enable activation ofthe system.

Referring to FIGS. l-4, the form of the selector unit illustrated hereinincludes a mounting bracket 124 suitably secured to a fixed portion ofthe vehicle in the drivers compartment, such as by screws fastened tothe underside of the instrument panel 126. The bracket includes adownturned portion or plate 128 which is secured, as by screws, to acover or cup member 130 to form a chamber 132. A bushing 134 is suitablysecured to plate 128, as by staking or soldering, and includes a bore toguide and support a shaft 136 for axial movements in relation to thebushing. The shaft extends through chamber 132 and also through aclearance hole in cover 130 and carries a pinion gear 138 suitablysecured to a portion of the shaft 136g having a reduced diameter toreceive the gear.

One or more -air vents, illustrated as holes 140, are

provided in cover radially equidistant from shaft 136. The holes arecovered and closed by a disc-valve 142 (FIGS. 2 and 3) inserted on thesmall diameter 136a of shaft 136 and retained by the gear between it andthe step in shaft 136.

The cover 130 includes two hose nipples 144 and 146 to receive tubes 120and 61', respectively. Nipple 144 is selectively covered or openedunrestrictively by -a valve body 154 supported by a stem or shaft 155made of any suitable rod or pin (FIG. l). The stem is secured to andsupported by plate 128 by suitable means, as by riveting, staking,soldering, etc., so that the stem is restrained from axial movements.The valve body 154 has suitably anged ends and slides with smallclearance on stern for axial movements in relation thereto for purposesto be described. An actuating disc 156 is suitably secured to shaft 136and extends between the flanged ends of valve body 154 to produce axialmovements thereof upon axial movements of the shaft 136, while enablingrotation of the shaft.

Any suitable speed-establishing means may be provided. In the form ofthe invention illustrated herein, a knob having a single tactile Brailleindicator 161 on its periphery is secured to shaft 136, as by a setscrew (FIG. 2), to facilitate axial and rotary movements of the shaft asrequired, to be explained.

Referring to FIGS. 2, 3 and 4, means are provided in the selector unitto translate rotary movements of the knob to axial movements of theflexible shaft 80 in any desired ratio. In the example shown herein,such means comprise a circular rack-piece 162 connected to the mountingbracket 124 for freely moving angular movements by a suitable hinge pin164. A conventional swivel 166, as used for carburetors, is hingeablysecured to rackpiece 162; and exible shaft 80 is inserted through theswivel and retained by the usual screw provided with the swivel, asshown. The sheath 81 is secured to the mounting bracket 124 by a clamp167 fastened by suitable means, as by a screw. In this manner, angularmovements of the rack-piece produce axial movements of the flexibleshaft.

Thus, the knob 160 is revolved by the driver to select the governedspeed, by causing such angular movements of the rack-piece to move shaft80 and vary the force 0f Speeder spring 62 as desired. A pair of stops168 are secured to (or are a part of) the mounting bracket 124 to limitthe rotary movement of the rack-piece so that the knob 160 can berotated only one complete turn. The same result may be achieved by anyother equivalent stop means, such as by limiting the shaft itself. Thenthe entire speed range of the speed-regulator mechanism is calibrated tofall within this one turn; this may be accomplished in the presentinvention -by varying the rate of spring 62 and/or varying the radialposition of the swivel 166 as desired. The driver memorzes the speedscorresponding to various clock positions of the tactile indicator 161.Thereafter, he rotates the knob by feeling the tactile indicator toestablish the correct clock position for the desired speed. In thismanner the driver can select the governed speed at any time withoutremoving his sight from the road. The tactile indicator in FIGS. 2 and 3is shown positioned at six oclock with the gear 138 in the middle of itstravel with respect to the rackpiece 162. In FIG. 1, the tactileindicator is shown in its twelve oclock position when the rack-piececontacts either of its stops 168. The rack-piece 162 includes anextension 16211 prebent to provide -a friction force when retained byhinge pin 164, to maintain knob 160 in any set rotary position. Asolenoid 147 is secured to a downturned portion 12411 of bracket 124 andincludes an armature 148 having a link 149 connected to extension 136abut adapted to enable rotation of yshaft 136. Referring to FIG. 5, thecircuit for solenoid 147 includes the vehicle battery 150 in series withthe parallel connection of the vehicle-doors, such as doors 151 and151', to control the 13 usual spring-biased switches 152 and 152',respectively. The vehicle door switches are in series with the usualdome light 153` which is provided in most automotive vehicles.

The valves 154 and 142 of the selector mechanism may be replaced by anyequivalent valve means such as a slide valve, or a spool valve slidingin a bore to control ports, etc., without changing the spirit of theinvention.

The selective control system also includes means to enable safeautomatic acceleration (sometimes called, Resume Speed) in a mannerwhich is initiated from a condition of normal driving, since the driversfoot initially must be on the accelerator. In the form of the inventiondisclosed in FIG. 9, the second component of the selective controlsystem as shown in FIGS. 1 and 9 comprises a valve unit 170 in a housing172 which is secured to the steering post 174 (or some other fixedportion of the vehicle) by a bracket 176. The housing includes hosenipples 178 and 180 to receive tubes 61 and 61', respectively (as shownonly in FIG. 9), for transferring manifold vacuum from the selector unitto the servo-motor. Referring particularly to FIG. 9, the valve unit 170includes a diaphragm 182 clamped between housing 172 and a cover 184 bysuitable means, as by screws, to form a pair of chambers 186 and 188. Abrake-operated activation valve 1'90 includes a flange portion securedto diaphragm 182 by bonding, or by a clamping action of a disc 192secured by rivets, or the like. Valve 190 includes a sealing portion ormember 194 adapted to open or close a port 196 communicating with vacuumtube 61' and tube 61. Valve 190 includes a stem 198 slidable in a borein cover 184 to enable axial movements of the valve while sealingchamber 188. The Valve stem includes an internal air passage 200 whichalways connects chamber 188 with only the upper end of valve 190, asshown in FIG. 9.

A bar 202 is hinged to a fixed support 204 to enable swingable movementsof the bar for actuating valve 190 biased by a spring 206 acting on thevalve. A rm leaf spring actuator 208 is secured to bar 202, as byrivets, and is mounted at -an angle to the bar to contact theengine-side of the brake arm in its idle position, as shown in FIG. 9.The actuator 208 is sufficiently firm that bar 202 normally moves asthough it were a rigid portion of the actuator. Whenever the brake pedalis depressed it acts on a suitable angle-portion of actuator 208 tocause swingable movements of bar 202 and axial movements of valve 190.If the valve unit 170 is mounted too close to the brake arm, valve 190would seat on port 196 before actuator 208 moves to the side of thebrake arm when it is fully depressed. In this event, the leaf spring 208merely bends suiciently to enable the full travel of arm 11 since thespring force of actuator 208 is much greater than the force of spring206. Also, a bleed-valve 210 is biased by a spring 212 and normallycloses an atomspheric air vent to chamber 188. The valve 210 includes astem 214 actuated by the bar 202 to open the bleed valve whenever theybrake pedal is depressed.

If desired for extra safety, the valve unit 170 may include a safetyshut-off valve 216 which is adapted to open or close a second port 218in series with valve 192 and its port 196. Valve 216, as exemplified inFIG. 9, comprises a ball supported by a stem 220 secured to a pressuresensitive member illustrated as a movable disc 222. The disc seats on asurface of housing 172 to form a chamber 224 which communicatesunrestrictedly with chamber 186 through a passage 226. Hence, the disc222 comprises a movable pressure-sensitive wall of chamber 224 and isbiased in a direction to open the chamber to atmosphere by a spring 228.The disc 222 includes -a lostmotion extension 230 which projects throughan aperture in bar 202 to cooperate therewith in a manner to bedescribed. The area of the disc and force of spring 228 are selected sothat a vacuum of only about l to 11/2 inch of mercury is suiicient tohold disc 222 closed and valve 216 open.

The overall operation of the control system will now be described,assuming the driver has entered the vehicle and started the engine withthe knob 160 in its olf position, in which all parts connected theretoare in their rightward position as would be viewed in FIG. 3. In thiscondition, the valve body shuts olf vacuum from tube so that atmosphericpressure exists in tube 61', tube 61 and in the valve unit 170. At thistime, referring to FIG. 9, valve 190 is held open by spring 206 sincethe pressures in chambers 186 and 188 are atmospheric; also, the spring228 forces disc 222 to open chamber 224 to the atmosphere and to holdvalve 216 on port 218. When the driver wants to activate the speedcontrol mechanism in the form shown, such as when the vehicle is inmotion, he must perform at least three deliberate and conscious steps toproduce such activation. First, the knob 160 is pulled out into its onposition at any desired vehicle speed, so that all parts connectedthereto stand in their leftward position, as shown in FIGS. l and 2. Atthis time, the left y end of gear 138 acts on disc-valve 142 to closethe air vents 140 and simultaneously open valve body 154 to transmit thefull undimnished manifold vacuum to chamber 132, tube 61 up to valve216, which is still closed.

The second deliberate action by the driver comprises the firstdepression of the brake pedal after pulling knob to its on position. Atthis rst brake-actuation, the bar 202 closes chamber 224 while openingvalve 216, so that manifold vacuum acts on disc 222 to maintain same inits closed position with valve 216 open as long as vacuum is supplied intube 61. This same brake-actuated movement of bar 202 acts on stem 198to close valve 190 on port 196. This action also opens the bleed valve210 so that atmospheric pressure exists in chamber 188, air passage 200,tube 61, chamber 44 and passages 56 and 55. At the same time, the fullmanifold vacuum is transmitted to chamber 186 and on the upper side ofdiaphragm 182 (as seen in FIG. 9) to overpower spring 206 and hold valvetightly closed against the port 196.

The third selective action by the vehicle-driver is performed wheneverthe driver chooses to effect nal activation of the speed regulatormechanism. If automatic acceleration is desired to a previously set orpreset speed of 65 m.p.h., for example, the driver normally acceleratesthe vehicle to a moderate speed such as 15420 m.p.h. so that valve 110is closed. Then the driver smoothly but firmly (in a deliberateselective operation) depresses the accelerator to temporarily openthrottle 16 and reduce the manifold vacuum suiiciently to enable spring206 to overpower the vacuum force of diaphragm 182. This action opensvalve 190 which enables the manifold vacuum to be transmitted throughtube 61 to the speed-regulator mechanism for activation thereof. At thistime the manifold vacuum is applied to both sides of diaphragm 182 sothat spring 206 thereafter holds valve 190 open at all subsequent valuesof manifold vacuum. The driver can now remove his foot from theaccelerator pedal (at a vehicle speed of about 20` m.p.h in thisexample), and the vacuum acts on diaphragm 40 to open the throttle whichcauses automatic acceleration from this lower speed. When the diaphragmis activated by this vacuum, a leaf spring clicker 232 carried by thediaphragm moves past the cover 41 to produce an audible click signal foradvising the driver that the regulator mechanism is activated. Thevehicle is then accelerated automatically up to the preselectedregulated speed established previously by pulling knob 160 when set toprovide the desired speed. When the preset governed speed is attained,the pilot valve 48 is automatically opened by the roller weights 90r tobleed air into chamber 44 through conduits 55 and 56; and thereafter thegovernor mechanism automatically maintains this preselected speed in thespeedregulating action at all loads, as previously described. Theoperator can override the governor action at any time 15 by depressingthe accelerator enabled by the lost-motion chain-link means 29, and whenhe removes his foot from the accelerator the vehicle speed returns tothe preset governed valve.

The valve of manifold vacuum that causes valve 190 to open uponadvancing the accelerator, as described in the preceding paragraph, isestablished by the force of spring 206 (for a given size of diaphragm).This value of manifold vacuum can be established initially in a verysmall range, but I have found values of 3.5 to inches of mercury to besatisfactory. If this vacuum is set at a higher value, such as 7-8inches of mercury, the accelerator is not depressed as much as for alower vacuum setting.

It is important to realize that this automatic engagement is effectedprimarily as a function of throttle position substantially independentof engine speed, because manifold vacuum predominently is a function ofthrottle position, particularly near road-load operation. If the driverdesires to accelerate manually, for example when he might be followingother vehicles temporarily, he depresses the accelerator moderately-thatis, only to positions providing values of vacuum above that forreleasing valve 190. I have found that by this means, the driveractually can exceed the preset speed without activating the regulatormechanism. This is very useful when following slow variable-speed trafc.When the traflic clears, the driver merely advances the accelerator asabove described until he hears the sound of clicker spring 232, and heagain removes his foot from the accelerator pedal. Another click signalis produced when the stem 198 strikes bar 202, which signal alsoindicates that activation has occurred.

When the brake pedal is depressed to retard vehicle speed, valve 190closes to shut off all vacuum to chamber 44, and then is held closed bymanifold vacuum as previously explained. Instantly the spring 46 movesdiaphragm 40 to its extreme leftward position out of the way of normalaccelerator movement, so that spring 26 moves the throttle to its idleposition. At this time, valve 48 is closed and valve 110 is again openedafter the vehicle speed reduces to zero. This brake release does notaffect valve 216 which remains open since the bar 202 merely slides onthe lost-motion stern 230. Since valve 154 remains open, the fullmanifold vacuum is maintained in chamber 132 if a door is not opened, sothat the selector mechanism is unaffected by depressing the brake pedal.When the brake pedal is released and valve 190 is held closed bydiaphragm 182, vacuum is not transmitted through tube 61 to orice 58. Inaddition while the vehicle is at rest, the governor mechanism ismaintained inactive because of the air-bleed past valve 110 aspreviously explained. In order to re-activate the governor mechanism, itis not necessary to reset knob 160 in any way. It is only necessary forthe driver to selectively advance throttle 16 (after the vehicle attainsa speed of 515 m.p.h. which causes valve 110 to close) to a positionthat lowers manifold vacuum to about 4 inches of mercury. This causesvalve 190 to be opened by spring 206 so that vacuum is transmittedinstantly to the orice 58, and the diaphragm 40 again opens the throttleto automatically accelerate the vehicle to the preset speed, asdescribed above.

Referring to FIG. 1, if desired, the value unit 170 may be installed intube 120 between the intake manifold and the selector unit 122. In thisevent, after the engine is started and `before knob 160 is pulled out,the value 190 is closed on port 196 at the first normal brake actuation,so that the brake pedal does not have to be depressed once after pullingout knob 160. However, the installation shown in FIG. l may bepreferable from a safety standpoint because an extra conscious effort isrequired of the driver after he deliberately pulls knob 160.

If the disc 222 is made smaller t release at 2 to 3 inches of mercury,for example, the regulator will be rendered inoperable automaticallyeach time the acceleral5 tor is depressed to Wide-open-throttleposition. This calibration can be used, if desired, to discourage hotrod acceleration.

It is also important to realize that the combination of the disc 222 andvalve 216 can be used by itself in any automotive speed regulatormechanism having source of pressure or vacuum to power the device. Inthis combination, the safety shut-off valve with the disc 222 acts as asafety mechanism to lock out the regulator mechanism after the manifoldvacuum dissipates; and requires a rst actuation of the brake pedal afterthe engine is started to enable activation of the regulator mechanism.

Restraining means are provided to automatically render the regulatormechanism inoperative to preclude any dangerous situation, for exampleWhenever there is a change of drivers. The main purpose of therestraining means is to enable the use of the automatic engagement oractivation means with automatic acceleration by preventing a dangeroussurprise factor Whenever there is a change of drivers, or even if thesame driver leaves the vehicle for extended periods and might forgetthat the device is ready to be engaged. For example, Without therestraining means and safety means, but with automatic engagement meansand automatic acceleration provided, if another driver enters thevehicle while the engine is idling, he might be surprised not knowingthat the speed regulator is engaged, or Worse, not even be aware thatsuch a device exists or is on the vehicle. The restraining meansdisclosed herein automatically causes the speed control device to berendered inoperative incident to normal selective operation of anelement of the vehicle by the driver, which selective operation normallyoccurs whenever there is a change in drivers (while the vehicle would beat rest) so that the desired result is accomplished.

In the examples illustrated herein, the restraining means includes or isoperated yby a selective vehicle element such as a vehicle door, or bymovement of the drivers seat, and/or transmission selector means. Theterms restraining means and selective vehicle element when used in theclaims all relate to the potentially dangerous condition when there is adriver-change with the speed-control device set for automaticactivation, occurring of course after the vehicle is brought to rest inthe examples disclosed herein. The control device is renderedinoperative incident to operation by the vehicle-driver of an elementwhich is a part of the vehicle, and is operable at his selectionnormally or usually when the vehicle is immobile, and accompanies achange in drivers or when one driver leaves the vehicle for a while andreturns later thereto.

The vehicle-element, illustrated herein is selective by the driver inthe sense that in normal operation of the vehicle, it is the driverschoice or selection to open a door, for example; and the speed-controldevice is automatically rendered inoperative incident to and as a resultof this selective movement of this vehicle-element, which selectivemovement normally accompanies a change in drivers as desired. In theforegoing example, normal operation of the vehicle is intended to coverany normal driver operation required between the times when the vehiclestands alone without a driver both before and after it is driven; andany element necessary to be operated by the driver selectively toperform such driveroperation between these times may be utilized if itqualifies broadly as above described.

The particular examples of restraining means illustrated herein comprisea combination including manually operted shut-off means. Therefore it isrst necessary to consider the manual shut-off action of the selectorunit 122 described above, as shown in FIGS. 1-4, Which might beconsidered as safety means. If at any time, the driver wishes to renderthe automatic throttle or governor action inoperative manually, hepushes knob in to the right, as viewed herein. As shown in FIGS. 1-3,the shaft 136 moves disc valve 142 to open the vents 140; andsimultaneously the valve body 154 is moved to cover the inlet of nipple144. At this instant, the knob is in the position shown in FIG. 3. Thevacuum instantly dissipates from chamber 132, tubes 61', 61, 56 andchamber 44, and diaphragm 40 is moved to the left out of operation aspreviously described. At the same time, the dissipation of vacuum ondisc 222 enables spring 228 to open the disc and close valve 216; thisaction exposes chamber 44 and passages 61, 55 and 56 to atmosphericpressure regardless of any other factors. The vacuum is cancelled untilknob 160 is pulled out and valve 216 is forced open and held open bydisc 222 after the engine is started and the brake pedal is againdepressed once. Hence, in order to set the speed regulator mechanismready for operation, the vehicle-driver must again deliberately pullknob 160 out into the position shown in FIG. 1. If this is performedwhile the vehicle is being driven, thel driver can activate theautomatic regulator as described above, but only after depressing thebrake pedal once.

Now consider the action of the restraining means illustrated in FIGS. 1,2 and 5. Whenever a vehicle-door 151 is opened for any reason, such asproduced by a change of drivers, the door switch 152 closes whichenergizes solenoid 147 and the usual dome light 153; this action causesarmature 148 to pull shaft 136 to the right, as shown in FIG. l, whichinstantly shuts olf all vacuum in chamber 132 and tube 61 in the samemanner as described above for the manual shutoff when shaft 136 is moved=by pressing knob 160 to the right. Also, as above described, the vacuumin the valve unit 170 dissipates so that valve 216 is closed. Any newdriver must deliberately and consciously pull knob 160 to enablesubsequent activation of the regulator mechanism by depressing the brakepedal once, and thereafter advancing the throttle until clicker 232 isheard. Then the foot can be removed from the accelerator and the vehiclewill automatically accelerate to and maintain the preset speed, untilthe brake pedal is depressed, or the knob 160 is pushed in, or the door151 is opened upon leaving the vehicle.

An alternate or supplemental restraining means is also disclosed inFIG. 1. In this form of restraining means a cam 234 is caused to revolvewhen the usual transmission selector shaft 235 rotates when moving thetransmission selector member from one position to another. In driveposition, the cam holds a valve 236 in a position to close a port 237 ofpassage 56. The valve is supported by a leaf spring 238 which is prebentto bias the valve open against the cam. When the transmission leverstands in drive position with valve 236 closed, the regulator mechanismoperates in a normal manner. Whenever the transmission selector lever ismoved out of drive position, valve 236 opens which bleeds in enough airto render the regulator mechanism inoperable until the selector memberis again moved into drive position.

The door operated restraining means is believed preferable because italways detects a change in drivers. While a transmission operatedrestraining means usually detects a change in drivers, sometimes adriver will stop the vehicle and leave the car with the engine idlingand with the parking brake locked while the transmission lever remainsin drive position. In this instance the transmission-operatedrestraining means will not detect a change in drivers. Also, with thedoor-operated restraining means, the driver must consciously pull knob160 after entering the vehicle and closing the door. The transmissionoperated restraining means does not affect knob 160, and the regulatordevice is operable after the transmission lever is moved into driveposition. Hence, this restraining means may be used to supplement thedoor-operated restraining means if the extra expense is justified.

A characteristic of manifold vacuum, as discussed previously, isutilized to enable relatively slow automaticacceleration following suchautomatic activation or engagement at a speed less than the governedspeed. In all carbureted engines, the manifold vacuum reduces from 18 ofmercury at full-load as the -throttle is opened. Such automaticacceleration is accomplished by the device shown in FIG. 1, according tothe present invention, by

selecting the spring 46 so that the diaphragm vacuum inl chamber 44 isnever more than a preselected value, such as 5 or linches of mercury forexample, which is a minimum for the manifold vacuum in this instance. Aspreviously explained the throttle opening at the minimum manifold vacuumcorresponding to this maximum diaphragm vacuum restricts theacceleration rate sufficiently to enable safe automatic acceleration. Ifthe spring 46 is selected to provide a workingtmaximum) diaphragm vacuumof 8-9 inches of mercury (or higher), the acceleration rate is evenslower after automatic-activation. However, this desirable result isaccomplished at the expense of reducing further the engine power atwhich the governed speed can be maintained.

It is important to appreciate that the parts in the vacuum supplycircuit (such as the passage in hose nipple 144, valve body 154, valveunit 170 and the tubes 120, 61' and `61) offer substantially noresistance or line-loss with all air-flows regardless of the openings ofvalves 64, 48 and 104. The only intended restrictions during normalspeed governor operation are at orifices 54 and 58, operating asdescribed in cooperation with valves `48 and 64, respectively. The airbleed itself is provided primarily to enable pilot valve 48 to controlpressure.

In the form of control system shown in FIG. l, a double-abutment ordouble-override linkage mechanism is provided. With this system,constructed as described above, when the governor override means 29operates throttle 16, as in FIG. 1, the accelerator override 35 enablesthe accelerator and its entire linkage (elements 20 and 21) to be biasedby spring 24 to stand in their idle position. Since the friction andinertia of the accelerator and its linkage does not have to beoverpowered by the speed governor mechanism, the size of servomotor 7can be substantially reduced. A smaller servo-motor will respond faster,since in the form shown in FIG. l, for example, less air must bedisplaced. Any servo-motor, regardless of the type of energy usedtherein, can be made to respond faster by reducing its size providingthe required forces are reduced. With a faster response, a speedgovernor mechanism is more stable without hunting An optional advantageof the double-abutment system is to maintain the size of theservo-motor, but select spring 46 to operate at much lower manifoldvacuum; then the regulator maintains the set speed at a higher enginepower. If the lostmotion unit 35 is replaced by a pin connection, thendiaphragm `40 must operate link 21 and accelerator 20 in itsspeed-regulating movements.

-I have observed in my own driving of speed control devices that whentraversing highway curves, there is a tendency to continue at the presetspeed even if the rate ought to be reduced 5 to 10 m.p.h. for safetypurposes. Several means are disclosed herein to sense the radius ofhighway curvature and automatically reduce vthe speed temporarily asrequired on such highway curves. One form of such curve compensationmeans, as disclosed in FIG. 1, comprises a weight 240 secured to a plate242 pivoted for angular movements to the left or right of the directionof the vehicle (viewed from above in FIG.

"1). A pair of links 244 and 246 have diametrically opposite lost-motionconnections with plate 242. The links 244 and 246 are hingably conectedto arms 248 and 250, respectively, which in turn are hinged to pinssecured to the walls of an extension cover 77a. One arm includes a pin252 cooperating with a slot of the other arm and is connected to aspring 254 attached to the swingable arm 49. Spring 254 is very light inrelation to Speeder spring 62 so that the movement of arm 248 onlyvaries the regulated speed a small amount.

The curve compensation device operates as follows during automaticthottle operation: On straight roads,

about 19 inches of mercury at rio-load to about one inch 75 the Weightis maintained in its central position by the force of spring 254. In aright curve, weight 240 moves upwardly (FIG. 1) which pulls arm 250 andextends spring 254 an amount dependent on the radius of highwaycurvature; at this time, arm 248 and link 244 are carried along in alost-motion action. The extension of spring 254 causes valve 48 to openslightly which reduces the regulated speed such as 5 to 10 m.p.h.; agreater highway curvature causes a greater temporary speed reduction. Asthe highway straightens out, the weight 240 gradually returns to itscentral position to gradually restore the preset governed speed. Whenthe highway curves to the drivers left, the reverse action occurs;weight 240 moves to the right because of centrifugal force (downwardlyin FIG. l) whch' pulls link 244 and arm 248 to extend spring 254 anamount dependent on the radius of highway curvature; arm 250 and link246 are carried in a lost-motion action. The speed is temporarilyreduced by extending spring 254, and the preset speed is restored as thehighway straightens out.

The curve-compensation means provides another safety factor in additionto the actual automatic reduction of speed in curves. This second safetyfactor is that the periodic and automatic change in speeds tends toreduce the possibility of so-called, highway-hypnosis.

MODIFICATIONS OF FIGS. -16

FIGS. 10-16 are modifications of the form of the invention shown inFIGS. 1-9. FIG. 10 shows a modified restraining means in which thesolenoid 147 is controlled by a switch 260 operated by the Vehicle seat262. The switch is arranged to pass across a circuit contact wheneverthe vehicle-driver rests on the seat and also when he leaves the seat.The electrical contact is made only temporarily in each movement of theseat (which is a movable vehicle element). Thus, the solenoid 147 isenergized each time the driver enters or leaves the vehicle to renderthe speed regulator mechanism inoperative in a manner described above.

FIG. 1l is another form of transmission-operated restraining means inwhich the usual transmission lever 262 operates the conventional links264 and 266 to the transmission. Link 264 includes a pair of cam-actingtabs 268 which individually operates a pin 272 only when the selectorlever is moved out of (and into) drive position; this action closes aswitch 274 biased open by a spring 276 and which energizes solenoid 147to render the speed regulator mechanism inoperative in a mannerdescribed above. Since the switch is closed only when lever 64 is inmotion adjacent the drive position of selector 262, switch 274 is alwaysopen in all other positions of the selector lever. As stated previously,it is presently believed that the transmission operated restrainingmeans is best suited to provide a supplemental safety action. Hence, theswitch 152 operated by a door 151 is connected in parallel with switch274 to operate solenoid 147 in a manner described above.

FIGS. 12 and 13 disclose another supplemental restraining means whichmay be added to provide more safety action, if warranted by the extraexpense. The form of selector machanism illustrated in FIGS. 12 and 13of the present invention comprises means forming a chamber adapted to besealed by a cover to contain air under vacuum which maintains the sealwhen the manuallyoperated means is moved to provide such transfer ofvacuum; the cover forms one or more walls of the chamber andis movablewith and by the manual means to open the chamber to atmosphere and breakthe vacuum when the manual means stands in its inoperative position.

`In the modification of FIGS. l2 and 13, the cover 130' is not securedto plate portion 128, but is movable away therefrom, as shown in FIG.13, by a pair of springs 158. At this time, chamber 132 is open to theatmosphere. The cover includes a sealing member 159, such as a gasket.

When the vehicle is at rest, the cover 130 is separated from plate 128by the springs 158, as shown in FIG. 13;

at this time a valve 280 closes an orifice 282. After the engine isstarted, vacuum is produced in tube only to the valve 280, and the coverremains in the position shown in FIG. 13. When the driver pulls the knob160, the left end of gear 138 acts on disc-valve 142 (FIG. 3) to forcethe cover against plate 128 to form and close the chamber 132, and allparts are then in the position shown in FIG. 12. At this time theorifice 282 is open, and substantially the full manifold vacuum istransmitted to chamber 132, and tube 61. The vacuum in chamber 132 actson the full exposed inside area of the cup-shaped rectangular cover 130to overpower the force of springs 158. Thus the vacuum itself acts tohold the cover to close chamber 132 as long as sufficient vacuum ismaintained therein.

When the engine is shut off, the manifold vacuum dissipates in sourcetube 120. Without vacuum in chamber 132, the springs 158 move the cover130 to the position shown in FIG. 13. This action carries the knob 160to the position 160 (FIG. 3), but it also can be forced to this positionby the driver any time he decides to render the speed controlinoperative. At this time, valve 280 closes orivce 282, and with thelarge gap in chamber 132, the operator must again deliberately pull knob160 into the position shown in FIG. 12. If this is performed While thevehicle is `being driven by the operator, the cover is held in its readyposition and the automatic throttle can be activated as before, but asillustrated herein, only after depressing the brake pedal once. Sincethis restraining means is operated by an engine function, it preferablyis used to supplement the door-operated restraining means.

FIG. 14 is a modification of FIG. 1 in which means are provided toretard the rate of acceleration, and which also can provide surgelessregulation, even for a reverse or negative speed droop. Referring toFIGS. 1 and 14, a fluid delay mechanism is inserted between speederspring 62 and a control spring 288 suitably secured to a retainer 289connected to flexible shaft 80. The delay mechanism comprises a pair ofdiaphragms 290 and 292 sealably enclosing a housing 294 having apartition or wall 296. The partition forms two chambers 298 and 300enclosed by diaphragms 290 and 292, respectively, `acting as movablewalls for the chambers. A small fixed orifice 302 (which could bemanually adjustable) is provided in partition 296 to restrict fluid flowbetween the chambers. A shaft 304 slides in a bore of the housing totransmit forces between diaphragm 292 and spring 62. Control spring 288is secured at one end to diaphragm 290 so that it can act both as atension and compression spring. An air bleed passage 306 communicateswith passage 5S and includes a pair of orifices 308 and 310 to controlpressure therebetween acting on diaphragm 292. Atmospheric air entersorifice 310 and may be controlled by a valve 312 biased by a spring 314;and the air then flows through orifice 308 into passage 55 subjected tovacuum which induces the air-bleed through passage 306. A vacuum acts ondiaphragm 292 which produces a force acting on spring 62. Anyforcesetting of control spring 288 is transmitted through the fluiddelay mechanism to the speeder spring 62, so the system is alwaysbalanced.

The operation to retard acceleration is as follows, referring to FIGS.1, 9 and 14: When the brake pedal is depressed and Vacuum dissipates intube 61, the vacuum in passages 56 and 306 also is cancelled. Thisaction reduces the force on the Speeder spring 62 which then movesdiaphragm 292 to the left (FIG. 14) to displace oil from chamber 300 to298. After the driver manually accelerates the vehicle slightly and thendepresses the accelerator temporarily to cause brake valve to open, thevehicle starts to accelerate automatic-ally. But now the speeder spring62 is at a low force 'which slowly increases as the vacuum from passage306 pulls diaphragm 292 to the right (FIG. 14) only as fast as oil flowsfrom chamber 298 to chamber 300 until the balanced setting of speederspring 62 is restored t0 the Valve set by shaft 80. Hence the rate ofautomatic acceleration is retarded to an extent determined by orice 302,in which a smaller orice reduces the acceleration rate.

In the foregoing action, the ball valve 312 and spring 314 can bearranged to provide only acceleration delay, or in addition to providespeed 'droop control. If spring 314 is of low rate, a constant vacuum ismaintained on diaphragm 292 Iwhenever vacuum exists in passage S; thiscondition would prevail for the example described above. As the rate ofspring 314 is increased, the action of valve i312 changes toward thecondition of a xed oriffice as would be produced by orifice 310` alone.This effects a slight but gradual increase in vacuum on diaphragm 292 asa function of the increase in vacuum in passage 55 (and chamber 44)which, in turn, is a function of an increase of throttle opening. Hence,as the throttle opens during regulator operation, the vacuum ondiaphragm 292 increases, although by a lesser amount. This actionincreases the vforce of the speeder spring 62 as the throttle opens,which approaches isochronous operation or even a reverse speed droop.The governing action is completely stable, even with a negative droop,because of the fluid delay mechanism. |In the foregoing example, if thestable speed at full load is higher than at no load because of the resetaction, the throttle is delayed in its increase to the higher speed toadvance only as fast as the engine speed can accelerate to this highervalue. This delay is cause-d by the restrictive effect of orifice 302 inretarding compression of spring 62 when the increased vacuum acts ondiaphragm 292. Without this delay mechanism, in a reverse speed droop,the throttle would snap open instantly before the engine can acceleratecannot surge. If the load decreases, the reset action is reversed whichcauses the regulated speed'to decrease slightly.

I have found that a slight negative speed droop of a few miles per hourprovides a continuous subconscious surprise when driving on turnpikeswhich tends to prevent highway hypnosis. However, this novel resetaction can prevent surging during isochronous operation or with anyother speed droop in all production units.

FIG. 15, which is viewed from the top of the vehicle, discloses amodified curve-compensation mechanism which has the advantage ofseparate installation; this enables the device to be added for moreexpensive vehicles and omitted from lower cost vehicles. In FIG. l5, anormally closed bleed valve 316 is biased open by a spring 318 to rideon a cam 320 carried by a weight 322 secured to an arm 324 fulcrummed ata support 326 for swingable movements. A pair of springs 328 and 330 aresecured at one end to arm 324 and at another end to fixed supports.

In operation, when the highway curves to the right, the centrifugalforce of weight 322 causes movement thereof to the left (upward in FIG.,which causes valve 316 to open and bleed air into passage '56. Thisaction reduces the regulated speed by an amount which increases as thehighway curvature increases. The weight gradually returns to theposition shown as the highway straightens out which shuts the air bleedat valve `316 to restore the original speed. When the highway curves tothe left the curve compensation action reverses.

FIG. 16 discloses another modified curve-compensation means in which theair bleed valve 316 is normally closed and supported by a leaf spring332 xed at one end and prebent to bias the valve in an openingdirection. The valve abuts a longitudinal cam 334 operated by a portionof the steering linkage such as the steering wheel shaft, or thesteering link 336 as illustrated in FIG. 16. In operation, whenever thehighway curves to the left, the steering wheel is turned to the leftwhich moves link 336 to the right (as in FIG. 16). This action enablescam 334 to open bleed valve 316 which reduces the governed speed as afunction of an increase in highway curvature in the same manner as forthe modification of FIG. 15. When the steering wheel is returned tonormal, valve 316 gradually closes to return the regulated speed to thehigher value established by rotation of knob 160. When the highwaycurves to the right, the curve compensation reverses.

In considering the overall speed control system now completely describedabove, it is apparent that an additional advantage in the inherentsimplicity of installation. The selector unit 122 is secured to theunderside of any instrument panel, as by sheet metal screws. The brakevalve unit is clamped to the steering post and made adjustable so thatactuator 208 is tangent to the usual suspended brake arm of any car, andit is not necessary to connect parts to the brake arm. The sensor-brainunit is connected in series to the conventional speedometer shaft. Onlyone bracket is necessary to support the servomotor unit 7, which iseasily connected by chain 29 having an adjustable clamp or bracketsecurable to the carburetor lever, or any movable part of theaccelerator carburetor linkage. The wires of solenoid 147 are connectedto the door switch circuit, standard in all automobiles.

Also, the Braille or touch system of speed-setting is particularlyuseful in combination with the automatic acceleration action describedabove. The driver can feel the tactile indicator to set the desiredspeed (with surprising accuracy) without moving his sight from the road.After pulling the knob and depressing the brake pedal once, the driveraccelerates the vehicle by mild depression of the accelerator until alow speed such as 10-15 m.p.h. is attained. At any desired speed lessthan the preset speed, he then depresses the accelerator smoothly butrmly until a click is heard, and removes his foot from the accelerator.The regulator then automatically accelerates the vehicle to the presetspeed and maintains this speed until cancelled by depressing the brakepedal. The entire improved operation is accomplished by the sense oftouch without any visual aids or reference lines. v

What is claimed is:

1. In a speed control device for automotive vehicle including an enginehaving control means therefor normally advanced to increasevehicle-speed, and conversely, said vehicle including brake-actuatingmeans, and including a source of energy, the combination comprising; aregulator mechanism for eifecting automatic regulating movements of saidcontrol means in a direction tending to maintain a preselected regulatedvehicle speed, said mechanism including servo-motor means operativelyconnected to said control means for causing said speed-regulatingmovements thereof, said regulator mechanism also including sensing meansresponsive to changes in a signal accompanying a change in vehicle speedto produce forces varying as a function of vehicle speed, pilot meansresponsive to changes in the sensing means forces for directing at leasta portion of said energy to said servornotor for causing said speedregulating movements thereof., biasing means acting on said pilot meanswith a predetermined force manually adjustable selectively by thevehicle-driver to establish said preselected regulated vehicle speed,release means operated by said brake-actuating means upon normalmovements thereof to at least temporarily inactivate said regulatormechanism with respect to said control means, and delay meansoperatively associated with said biasing means to restrict the rate ofchange of said force thereof whenever same is readjusted by said driverto select a new preselected vehicle speed.

2. The combination of means defined in claim 1, and said delay meansincluding diaphragm means acting on said biasing means and forming twofluid chambers, said diaphragm means including a pair of diaphragmsrespectively enclosing and sealing each of said chambers, orice meansconnecting said chambers to enable lluid t0 flow from one chamber to theother chamber upon a change of force on one of said diaphragms, a firstof said two diaphragms acting on said biasing means, and manuallyselectable means acting on said second diaphragm to pressurize saidfluid for establishing said predetermined adjustable force acting onsaid biasing means with a delayed response of said first diaphragm whensaid uid is caused to flow through said orice means to cause saidrestricted rate of change of said force of said biasing means.

3. In a speed control device for an automotive vehicle including anengine having control means therefor normally advanced to increasevehicle-speed, and conversely, said vehicle including brake-actuationmeans, and including a source of energy, the combination cornprising; aregulator mechanism for eecting automatic regulating movements of saidcontrol means in a direction tending to maintain a preselected regulatedvehicle speed, said mechanism including servo-motor means operativelyconnected to said control means for causing said speed regulatingmovements thereof, said regulator mechanism also including sensing meansresponsive to changes in a signal accompanying a change in vehicle speedto produce forces varying as a function of vehicle speed, pilot meansresponsive to changes in the sensing means forces for directing at leasta portion of said energy to said servo-motor for causing said speedregulating movements thereof, biasing means acting on said pilot meanswith a predetermined force to establish the speed of the vehicle,activating means operatively associated with said mechanism andinitiated selectively by the vehicle-driver entirely at his discretionto automatically cause activation of said mechanism with respect to saidcontrol means at a speed lower than said preselected speed, releasemeans operated by said brake-actuating means upon normal movementsthereof for rendering said regulator mechanism inactive but notinoperative with respect to said control means, said regulator mechanismbeing constructed and arranged to effect automatic acceleration of thevehicle from said lower speed to said preselected speed and tendingautomatically to maintain said preselected regulated speed thereafter,delay means operatively associated with said biasing means and saidactivating means to change said biasing force when the vehicle speedreduces as a result of said normal movements of said brake-actuatingmeans, said delay means including means to return said biasing meansforce in a direction toward said predetermined value as a result of saidselective activation of said mechanism, and said delay means includingmeans to restrict the rate of said return of said biasing means force tosaid predetermined value for restricting the rate of said automaticacceleration.

4. In a speed control device for an automotive vehicle including anengine having control means therefor normally advanced to increasevehicle-speed, and conversely, and including vehicle brake-actuatingmeans, said vehicle having a source of iluid pressure, the combinationcomprising; a regulator mechanism operatively associated with saidcontrol means and including means operated by at least a portion of saiduid pressrue to produce forces acting on said control means in responseto a signal accompanying a change in the speed of the vehicle to effectautomatic regulating movements of said control means in a directiontending to maintain a preselected regulated speed of the vehicle, valvemeans operated by said brakeactuating means to effect a low value ofsaid pressure portion upon each actuation of said brake-actuating meansto render said regulator mechanism inactive but not inoperative, and toprovide a higher value of said pressure portion for reactivation of saidregulator mechanism selectively by the vehicle-driver upon advancingsaid control means after releasing said brake-actuating means, saidre-activation being effected at a vehicle speed lower than saidregulated speed, said regulator mechanism being constructed and arrangedto effect automatic acceleration of the vehicle from said lower speed tosaid regulated speed and tending automatically to maintain saidpreselected regulated speed thereafter, a uid delay device includingdiaphragm means subjected to said pressure portion to provide forcesacting on said regulator mechanism for establishing said preselectedspeed during said automatic regulating movements thereof and to changesaid diaphragm forces when said pressure portion is diminished uponactuation of said brake-actuating means, and said delay device includingfluid means to restrict the application of said diaphragm forces to saidregulator mechanism when a higher pressure portion is restored as aresult of said re-activation of said mechanism to restrict the rate ofsaid automatic acceleration.

5. The combination of means dened in claim 4, and said delay deviceincluding rst yieldable means acting on said regulator mechanism, twouid chambers, said diaphragm means including a pair of diaphragmsrespectively enclosing and sealing each of said chambers, orifice meansconnecting said chambers to enable fluid to flow from one chamber to theother chamber upon a change of said pressure portion, a first of saidtwo diaphragms acting on said first yieldable means, and manuallyadjustable second yieldable means acting on said second diaphragm with adelayed response of said first diaphragm when said fluid is caused toHow through said orifice means after said higher value of said pressureportion is restored to establish said preselected regulated speed.

6. In a speed control device for an automotive vehicle including anengine having control means therefor, the combination comprising; aregulator mechanism operatively associated with said control means andadapted to produce forces acting thereon in response to a signalaccompanying a change in vehicle speed to effect automatic regulatingmovements of said control means in a direction tending to maintain apreselected regulated speed of the vehicle, said regulator mechanismincluding biasing means to establish said preselected speed, reset meansoperatively associated with said mechanism to provide a force formodifying said biasing means and varying as a function of the positionof said control means, and said reset means including means to delay theapplication of said modifying force to said biasing means upon anautomatic initial change of said control means resulting from a changein engine load to provide any desired speed drop with stability.

7. In a speed control device for an engine having control meanstherefor, the combination comprising; a regulator mechanism operativelyassociated with said control means and adapted to produce forces actingthereon in response to a signal accompanying a change in engine speed toeffect automatic regulating movements of said control means in adirection tending to maintain a preselected regulated speed of theengine, said regulator mechanism including a spring to establish saidpreselected speed, reset means operatively associated with saidmechanism to provide a force acting directly on said spring and varyingas a function of the position of said control means, and said resetmeans including means to delay the application of said last-named forceto said spring upon an automatic initial change of said control meansresulting from a change in engine load to provide any desired speeddroop with stability.

8. In speed control device for an automotive vehicle including an enginehaving control means therefor normally advanced to increasevehicle-speed, and conversely, and including vehicle brake-actuatingmeans, said vehicle including means providing a fluid pressure thatvaries as a function of the position of said control means, thecombination comprising; a regulator mechanism operatively associatedwith said control means and adapted to produce forces acting thereon inresponse to a signal accompanying a change in the speed of the Vehicleto effect automatic regulating movements of said control means in adirection tending to maintain a preselected regulated speed of thevehicle, said regulator mechanism including biasing means manuallyadjustable by the Vehicle-driver to provide forces for establishing saidpreselected speed, release means operated by said brake-actuating meansupon normal movements thereof to at least temporarily inactivate saidregulator mechanism with respect to said control means, and reset meansincluding fluid time delay means operatively associated with saidbiasing means, said reset means including means having a delayedresponse to changes in said varying pressure to affect said forcesprovided by said biasing means to delay an automatic change of saidcontrol means resulting from a change in engine load for providing anydesired speed droop with stability.

9. The combination of means defined in claim 8, and said delay meansincluding diaphragm means acting on said biasing means and-forming twofluid chambers, said diaphragm means including a pair of diaphragmsrespectively enclosing and sealing each of said chambers, orice meansconnecting said chambers to enable fluid to flow from one chamber to theother chamber upon a change of force on one of said diaphragms, one ofsaid two diaphragms acting on said biasing means to produce said forcesthereof, said Varying pressure disposed to act on one of said diaphragmsto pressurize said tluid for modifying said biasing means force with adelayed response of said last-named one diaphragm when said fluid iscaused to ow through said orifice means to cause said restricted rate ofchange of said biasing means force for providing any desired stablespeed-droop.

10. In a speed control device for an automotive vehicle including anengine having control means therefor normally advanced to increasevehicle-speed, and conversely, the combination comprising; a regulatormechanism for effecting automatic regulating movements of said controlmeans in a direction tending to maintain a preselected regulated vehiclespeed, said mechanism including pressure-responsive means operativelyconnected to said control means for effecting said speed-regulatingmovements thereof, a fluid circuit having a source of fluid pressure foroperating said pressure responsive means, said regulator mechanism alsoincluding sensing means `responsive to changes in a signal accompanyinga change in vehicle speed to produce forces varying as a function ofvehicle speed, said mechanism including valve means responsive tochanges in the sensing means forces for controlling pressures in saidcircuit acting on said pressure-responsive means for causing saidspeed-regulating movements thereof, said valve means including a movablevalve member and a mating member cooperable therewith, the configurationof said valve member in relation to said mating member being adapted toproduce modulated pressures acting on said pressure responsive means andvarying as a function of the position of said valve member, saidmechanism including biasing means to provide forces acting on said valvemeans to establish the speed of the vehicle, reset means includingpressuresensitive means acting on at least a portion of said biasingmeans, said modulated pressures being disposed to act on saidpressure-sensitive means in a direction enabling changes of saidmodulated pressures to cause a reset of vehicle-speed in a reduced speeddirection when the engine load reduces, and conversely, said reset meansincluding delay means for delaying said changes in said modulatedpressures acting on said pressure-sensitive means when said engine loadchanges to prevent responding movements of said control means fromexcessively preceding actual resulting changes in vehicle-speed duringsaid automatic speed-regulating action for providing stable regulationat any desired speed-droop.

References Cited UNITED STATES PATENTS 2,929,616 3/1960 FOX 137--362,966,224 12/1960 Teetor 123-103 2,990,821 7/1961 Cramer 251-54 X3,275,008 9/1966 Kerensky 137-36 3,426,777 2/ 1969 Plummer 251-54 XKENNETH H. BETTS, Primary Examiner

